A vacuum tube of the type mentioned in the first paragraph is known from U.S. Pat. No. 4,298,818. In this Patent the ceramic element consists of a ceramic support, the layer consists of a metallized pattern on the ceramic support and the conductive element is an electrode of the electron gun, and the connection is formed by a soldered joint between the electrode of an electron gun and the metallized pattern.
During the various steps in the manufacture of vacuum tubes temperatures up to approximately 400.degree. C. occur. Such temperatures may cause damage to the soldered joint between the electrode and the metallized pattern and may lead to a breakdown of the vacuum tube. At such temperatures it is also possible that a soldered joint releases gases causing the gas pressure in the vacuum tube to rise, which adversely affects the life cycle of the vacuum tube. Moreover, soldering is a relatively time-consuming and costly process. Hereinbelow, the term "conductive" is to be understood to mean electrically conductive, unless stated otherwise.